This section is intended to provide a background or context to the invention that is recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
The ability to cryopreserve and then reanimate oocytes, embryos or blastocysts is desirable for many reasons. However, conventional techniques have proven difficult to reproduce in an effective, efficient and consistent manner. Such conventional techniques are typically labor-intensive, requiring substantial handling of the oocytes, embryos or blastocysts by a highly skilled human technician. For example, conventional cryopreservation of an oocyte requires that the technician manually move the oocytes from one location to another in the cryopreservation process, such as from incubation to washing solution to a cryoprotectant solution. Further, oocytes frequently incur structural damage during conventional cryopreservation techniques. For example, conventional manual movement of oocytes among cryopreservation solution baths can impart osmotic and thermal shock. For instance, formation of ice crystals within the oocyte can cause intracellular damage in the oocyte. Oocytes undergoing conventional cryopreservation techniques can also experience a loss of sphericity and undesirable changes in volume. Such effects may result in structural damage in addition to toxicity, thereby significantly diminishing the viability of the oocyte and ultimately reducing the probability of successful fertilization.
Human involvement and conventional preservation techniques greatly contribute to the lack of consistency in cryopreservation of oocytes, embryos or blastocysts and results in an undesirably low fertilization success rate. Therefore, it is desirable to provide a partially automated method and system for the repeatable and efficient cryopreservation and reanimation of oocytes, embryos or blastocysts that mitigate effects harmful to the viability of the oocyte, embryo or blastocyst, and thereby increasing the rate of successful fertilization.